90's Durango - Mechanic told friend to scrap

408 swinger said
The 5.2/5.9 engines have chains just like their LA brethren. The 4.7 OHC V8 uses multiple chains. No belts in V8s. Could be about anything from plugged cats to bad alternator to bad fuel. His mechanic sounds like a complete dickweed.

I agree. I was gonna get by and do a compression check and check for fuel pressure and spark. Simple stuff.